Background Rheumatoid arthritis (RA) has been associated with an increased risk of cardiovascular (CV) morbidity and mortality. Recent data indicated that this could also be the case in psoriatic arthritis (PsA) and axial spondyloarthritis (AxSpA) patients.
Objectives To compare the risk of major adverse cardiovascular events (MACE) in RA, PsA and AxSpa as of disease onset.
Methods A mixed retrospective and prospective cohort study was conducted using data from patients included in the Swiss Clinical Quality Management (SCQM) registry. Patients diagnosed with RA, PsA, or AxSpA at an age of ≥18 years without a history of MACE (i.e., non-lethal myocardial infarction, non-lethal stroke and death from cardiovascular event) at the time of first articular symptoms or, if not available, at the time of diagnosis were included. The primary outcome was the incidence of first MACE, using self-reported or physician-reported data. For each patient we recorded the time in years from disease onset until either occurrence of first MACE or end of follow-up. The exposure of interest was the type of rheumatic disease: RA, PSA or AxSpA. In addition to sex and age at disease onset, we assessed traditional CV risk factors: known familial history of MACE before age 50, and presence of ever-hypertension, ever-diabetes, ever-hyperlipidemia, and ever-smoking. We applied Poisson regression to estimate and compare the incidence rates for MACE.
Results 5311 patients (3068 RA, 1462 AxSpA, and 781 PsA patients) were eligible and contributed a total follow-up time of 37'459 years for RA, 19'818 for AxSpA, and 9'159 for PsA. Diseases started between 1950 and 2014 and differed significantly with respect to assessed CV risk factors (Table 1). A total of 98 RA, 28 AxSpA, and 11 PsA patients had experienced at least one MACE since disease onset. The unadjusted incidence rate of MACE per 1000 person-years was 2.62 for RA, 1.41 for AxSpA, and 1.20 for PsA (p=0.0011). After adjusting for traditional CV risk factors, age at disease onset, sex, and year of disease onset (categorized as: <1985, 1985–2000, or >2000) the significant difference between PsA and RA persisted (MACE incidence rate ratio (IRR): 0.45, 95% confidence interval (CI): 0.22- 0.91), while the difference between AxSpA and RA was decreased and no longer significant (IRR: 0.86, 95% CI: 0.5 -1.49). Because ever-hypertension, ever-diabetes, ever-hyperlipidemia, and ever-smoking may not reflect the status at time of disease onset, we analyzed the risk of MACE also with only adjusting for sex, age at disease onset, disease onset and family history of early MACE. The results (n=5311) were very similar, suggesting that especially age and sex are important confounders when comparing incidence rates across diseases. Male sex, older age at disease onset, a known family history of early MACE, ever-hypertension, and ever-hyperlipidemia were also significantly positively associated with the risk of MACE.
Conclusions Taking into account traditional CV risk factors, age and sex, the type of rheumatic disease remained associated with risk of MACE. RA seems to convey a larger CV risk than PsA, while the difference between RA and AxSpA remains unclear.
Disclosure of Interest None declared